svn commit: r220443 - head/sys/dev/ath/ath_hal
Adrian Chadd
adrian at FreeBSD.org
Fri Apr 8 07:44:00 UTC 2011
Author: adrian
Date: Fri Apr 8 07:44:00 2011
New Revision: 220443
URL: http://svn.freebsd.org/changeset/base/220443
Log:
Begin fleshing out a public HAL routine to export the per-chain
ctl/ext noise floor values.
This routine doesn't check to see whether the radio is MIMO
capable - instead, it simply returns either the raw values,
the "nominal" values if the raw values aren't yet available
or are invalid, or '0' values if there's no valid channel/
no valid MIMO values.
Callers are expected to verify the radio is a MIMO radio
(which for now means it's an 11n chipset, there are non-11n
MIMO chipsets out there but I don't think we support them,
at least in MIMO mode) before exporting the MIMO values.
Modified:
head/sys/dev/ath/ath_hal/ah.c
head/sys/dev/ath/ath_hal/ah.h
Modified: head/sys/dev/ath/ath_hal/ah.c
==============================================================================
--- head/sys/dev/ath/ath_hal/ah.c Fri Apr 8 06:58:01 2011 (r220442)
+++ head/sys/dev/ath/ath_hal/ah.c Fri Apr 8 07:44:00 2011 (r220443)
@@ -893,6 +893,76 @@ ath_hal_getChanNoise(struct ath_hal *ah,
}
/*
+ * Fetch the current setup of ctl/ext noise floor values.
+ *
+ * If the CHANNEL_MIMO_NF_VALID flag isn't set, the array is simply
+ * populated with values from NOISE_FLOOR[] + ath_hal_getNfAdjust().
+ *
+ * The caller must supply ctl/ext NF arrays which are at least
+ * AH_MIMO_MAX_CHAINS entries long.
+ */
+int
+ath_hal_get_mimo_chan_noise(struct ath_hal *ah,
+ const struct ieee80211_channel *chan, uint8_t *nf_ctl,
+ uint8_t *nf_ext)
+{
+ HAL_CHANNEL_INTERNAL *ichan;
+ int i;
+
+ ichan = ath_hal_checkchannel(ah, chan);
+ if (ichan == AH_NULL) {
+ HALDEBUG(ah, HAL_DEBUG_NFCAL,
+ "%s: invalid channel %u/0x%x; no mapping\n",
+ __func__, chan->ic_freq, chan->ic_flags);
+ for (i = 0; i < AH_MIMO_MAX_CHAINS; i++) {
+ nf_ctl[i] = nf_ext[i] = 0;
+ }
+ return 0;
+ }
+
+ /* Return 0 if there's no valid MIMO values (yet) */
+ if (! (ichan->privFlags & CHANNEL_MIMO_NF_VALID)) {
+ for (i = 0; i < AH_MIMO_MAX_CHAINS; i++) {
+ nf_ctl[i] = nf_ext[i] = 0;
+ }
+ return 0;
+ }
+ if (ichan->rawNoiseFloor == 0) {
+ WIRELESS_MODE mode = ath_hal_chan2wmode(ah, chan);
+ HALASSERT(mode < WIRELESS_MODE_MAX);
+ /*
+ * See the comment below - this could cause issues for
+ * stations which have a very low RSSI, below the
+ * 'normalised' NF values in NOISE_FLOOR[].
+ */
+ for (i = 0; i < AH_MIMO_MAX_CHAINS; i++) {
+ nf_ctl[i] = nf_ext[i] = NOISE_FLOOR[mode] +
+ ath_hal_getNfAdjust(ah, ichan);
+ }
+ return 1;
+ } else {
+ /*
+ * The value returned here from a MIMO radio is presumed to be
+ * "good enough" as a NF calculation. As RSSI values are calculated
+ * against this, an adjusted NF may be higher than the RSSI value
+ * returned from a vary weak station, resulting in an obscenely
+ * high signal strength calculation being returned.
+ *
+ * This should be re-evaluated at a later date, along with any
+ * signal strength calculations which are made. Quite likely the
+ * RSSI values will need to be adjusted to ensure the calculations
+ * don't "wrap" when RSSI is less than the "adjusted" NF value.
+ * ("Adjust" here is via ichan->noiseFloorAdjust.)
+ */
+ for (i = 0; i < AH_MIMO_MAX_CHAINS; i++) {
+ nf_ctl[i] = ichan->noiseFloorCtl[i] + ath_hal_getNfAdjust(ah, ichan);
+ nf_ext[i] = ichan->noiseFloorExt[i] + ath_hal_getNfAdjust(ah, ichan);
+ }
+ return 1;
+ }
+}
+
+/*
* Process all valid raw noise floors into the dBm noise floor values.
* Though our device has no reference for a dBm noise floor, we perform
* a relative minimization of NF's based on the lowest NF found across a
Modified: head/sys/dev/ath/ath_hal/ah.h
==============================================================================
--- head/sys/dev/ath/ath_hal/ah.h Fri Apr 8 06:58:01 2011 (r220442)
+++ head/sys/dev/ath/ath_hal/ah.h Fri Apr 8 07:44:00 2011 (r220443)
@@ -951,6 +951,14 @@ extern HAL_STATUS __ahdecl ath_hal_set_c
HAL_CTRY_CODE cc, HAL_REG_DOMAIN regDmn);
/*
+ * Fetch the ctl/ext noise floor values reported by a MIMO
+ * radio. Returns 1 for valid results, 0 for invalid channel.
+ */
+extern int __ahdecl ath_hal_get_mimo_chan_noise(struct ath_hal *ah,
+ const struct ieee80211_channel *chan, uint8_t *nf_ctl,
+ uint8_t *nf_ext);
+
+/*
* Calibrate noise floor data following a channel scan or similar.
* This must be called prior retrieving noise floor data.
*/
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